Results During the 2-year follow-up, 66/186 patients (35%) had PTSD symptoms, with the greatest prevalence by the 3-month follow-up. Fifty-six patients with post-ALI PTSD symptoms survived to the 24-month follow-up, and 35 (62%) of these had PTSD symptoms at the 24-month follow-up; 50% had taken psychiatric medications and 40% had seen a psychiatrist since hospital discharge. Risk/protective factors for PTSD symptoms were pre-ALI depression [hazard odds ratio (OR) 1.96, 95% confidence interval (CI) 1.06–3.64], ICU length of stay (for a doubling of days, OR 1.39, 95% CI 1.06–1.83), proportion of ICU days with sepsis (per decile, OR 1.08, 95% CI 1.00–1.16), high ICU opiate doses (mean morphine equivalent ≥100 mg/day, OR 2.13, 95% CI 1.02–4.42) and proportion of ICU days on opiates (per decile, OR 0.83, 95% CI 0.74–0.94) or corticosteroids (per decile, OR 0.91, 95% CI 0.84–0.99).

Conclusions PTSD symptoms are common, long-lasting and associated with psychiatric treatment during the first 2 years after ALI. Risk factors include pre-ALI depression, durations of stay and sepsis in the ICU, and administration of high-dose opiates in the ICU. Protective factors include durations of opiate and corticosteroid administration in the ICU.